class Opal::Nodes::MassAssignNode

def compile_masgn(lhs_items, array, len = nil)
  pre_splat  = lhs_items.take_while { |child| child.type != :splat }
  post_splat = lhs_items.drop(pre_splat.size)
  pre_splat.each_with_index do |child, idx|
    compile_assignment(child, array, idx, len)
  end
  unless post_splat.empty?
    splat = post_splat.shift
    if post_splat.empty? # trailing splat
      if part = splat.children[0]
        helper :slice
        part = part.dup << s(:js_tmp, "$slice(#{array}, #{pre_splat.size})")
        push ', '
        push expr(part)
      end
    else
      tmp = scope.new_temp # end index for items consumed by splat
      push ", #{tmp} = #{array}.length - #{post_splat.size}"
      push ", #{tmp} = (#{tmp} < #{pre_splat.size}) ? #{pre_splat.size} : #{tmp}"
      if part = splat.children[0]
        helper :slice
        part = part.dup << s(:js_tmp, "$slice(#{array}, #{pre_splat.size}, #{tmp})")
        push ', '
        push expr(part)
      end
      post_splat.each_with_index do |child, idx|
        if idx == 0
          compile_assignment(child, array, tmp)
        else
          compile_assignment(child, array, "#{tmp} + #{idx}")
        end
      end
      scope.queue_temp(tmp)
    end
  end
end